1. Technical Field
The present disclosure relates to touch input technology on, and more particularly, to a method and apparatus for inputting keys in a virtual keypad.
2. Description
With the development of information technology, various portable terminals such as mobile phones, tablet PCs, multimedia players, palm consoles, personal digital assistants (PDA), GPS navigators and remote controls, etc. have already become a necessity of peoples' daily lives. People frequently use such terminals for web surfing, information publishing, image processing, e-mail, etc.
To provide a better user experience, manufacturers have made the screens of portable terminals increasingly larger in size. However, increasing screen size may make the entry of information in portable terminals more difficult. When the screen of a portable terminal exceeds a certain size, it is impossible for most users to both hold the terminal and input information into the terminal with the same hand. Thus, during normal use, portable terminals with larger screen sizes require to be held with two hands in the manner illustrated in FIG. 1.
If a user were to attempt operating a large-screen portable terminal with one hand only, the user may do so by using the technique depicted in FIG. 2. Namely, the user may employ the thumb of the hand holding the terminal to interact with the terminal's touch screen while using the remaining four fingers to support the phone. However, due to the thumb's limited length, the user may experience a blind spot when interacting with the terminal's touch screen. In the example of FIG. 2, the dashed circle indicates the portion of the terminal's screen that is within reach of the user's thumb, while all other parts of the screen are out of reach.
Nevertheless, there could be situations in which users need to operate their smart phones with one hand only. For example, a user may have to use one hand to operate his or her portable terminal when the other hand is dirty, or when the user is holding the handrail on a subway or a bus. Accordingly, the need exists for techniques that permit users to operate large-screen portable terminals with one hand only.